The present invention relates to an article of footwear having one or more ground-engaging members, especially an athletic shoe having one or more selectively alterable ground-engaging members (such as spikes, cleats, etc.).
It is generally known to provide one or more protruding ground-engaging members on the sole of a shoe, especially on the sole of an athletic shoe for activities such as golf, soccer, track, baseball, and xe2x80x9cAmerican-stylexe2x80x9d football. Such ground-engaging members are variously known in the art as cleats, spikes, studs, leaves, blades, triangles, nubs, etc., and generally serve to increase traction between the shoe and the ground surface.
Furthermore, it is conventionally known to use particular types of ground-engaging members for certain types of playing surfaces. For example, molded cleats made from hard rubber or a thermoplastic material are commonly used on hard/firm natural ground surfaces (e.g., hard dirt). Relatively smaller molded rubber nubs are commonly used on artificial turf and the like. Also, relatively thin spikes are conventionally used in golf and in track.
For activities taking place on soft ground (e.g., wet fields, soggy grass, or muddy ground), it is generally known to use removable ground-engaging members. This is done to enable the user to use differed sized ground-engaging members based on the type of field being played on, and the condition of the field. Conventional removable ground-engaging members are typically engaged with a shoe sole by way of cooperating screw threads or other rotational engagement.
When conventional removable ground-engaging members are provided with screw threads for engagement with a shoe, a separate tool is used to manually rotate a ground-engaging member to attach and remove the ground-engaging members as desired. This is generally time consuming and labor intensive, and is also problematic if a user decides to change ground-engaging members in a hurried manner, such as during the course of a game, for example.
Furthermore, conventional removable ground-engaging members must be adequately rotationally tightened so as to ensure good engagement between the shoe and the ground-engaging member. However, it is conventionally difficult to recognize when the ground-engaging member has been adequately tightened. Thus, the ground-engaging member may be inadvertently over-torqued in an attempt to ensure good engagement. This can damage the screw threads on the shoe and/or on the ground-engaging member, making it difficult or even impossible to subsequently disengage the ground-engaging member from the shoe when desired. On the other hand, the ground-engaging member may be inadvertently under-torqued (for example, to avoid damage caused by over-torquing). When this occurs, the ground-engaging member may not function as a stable traction device and/or may become loose and be susceptible to falling off of the shoe.
While some conventional ground-engaging members are not threadedly engaged with a shoe, they still suffer from structural and/or functional problems. In particular, some existing non-threaded ground-engaging members are free to rotate relative to the sole. This can be a problem when, for example, the ground-engaging member is axially asymmetrical in shape (for example, conical or frusto-conical) because free edges of an axially asymmetrical ground-engaging member can become exposed, caught on objects and such, and be torn away. Furthermore, relative movement between a ground-engaging member and a sole generally destabilizes the engagement between the ground-engaging member and the sole, compared to holding them fixed relative to one another.
Also, some existing ground-engaging members use a receiving portion or the like mounted on an exterior surface of the shoe sole. Thus, the receiving portion may possibly be sheared off the sole or may otherwise become dislodged.
The present invention is generally directed to an article of footwear (such as a shoe, and especially, but not necessarily only, an athletic shoe like a cleated soccer shoe) having a selectively alterable ground-engaging member engaged with a sole of the article of footwear, and a kit and method for altering ground-engaging characteristics of an article of footwear.
A ground-engaging member according to the present invention is preferably engaged with the sole in a non-rotational manner, such as by simply applying a substantially non-rotational linear force to engage the ground-engaging member with the sole. Such a non-rotational action can be ensured, for example, by providing a rotation preventing mechanism. For example, a rib, spline, ridge, etc. may be provided on one of the ground-engaging member and a corresponding portion of the sole, and a slot, groove, etc. is provided in the other of the ground-engaging member and the corresponding portion of the sole. The rib and slot cooperate in the process of engaging the ground-engaging member with the sole so the ground-engaging member can only be linearly moved into engagement with the sole, with substantially no relative rotation therebetween. Once the ground-engaging member is engaged with the sole, the rotation prevention mechanism additionally prevents subsequent relative rotation between the ground-engaging member and the sole.
According to one example of the present invention, one of the sole and the ground-engaging member includes a resilient spring assembly, and the other of the sole and the ground-engaging member includes a leg assembly having legs sized and arranged to resiliently retain the spring assembly therebetween.
When a ground-engaging member according to the present invention is engaged with the sole according to the present invention, it is desirable to provide a detectible feedback to indicate that the ground-engaging member is properly engaged with the sole. In a particular (but not exclusive) example of the present invention, the detectible feedback is an audible feedback (such as, without limitation, a snapping sound or a click sound) that a user can hear when the ground-engaging member is properly engaged with the sole. For example, in the above-described arrangement including spring and leg assemblies, the legs initially resiliently deflect the spring assembly. Subsequently, the spring assembly resiliently recovers, preferably in an audible manner, such as with a snap or click. Therefore, the spring assembly is resiliently retained between the legs of the leg assembly.
A ground-engaging member according to the present invention may include a selectively removable tip that is engaged with a portion of the sole in accordance with the foregoing description. Furthermore, each portion of the sole may be engageable with several such tips, at least some of which have different heights, such that a given tip may be replaced with another tip having a different height. In this manner, the characteristics (especially, but not necessarily only, ground-engaging characteristics) of the article of footwear may be adjusted quickly and assuredly in accordance with changing playing conditions by avoiding the time-consuming conventional process of using a screw tool to engage and disengage conventional ground-engaging members, while additionally permitting sure engagement of a ground-engaging member because of the detectible feedback provided in accordance with the present invention.
As mentioned above, the ground-engaging member can be engaged with a sole using a simple, non-rotational pressing force (especially, but not necessarily only, a manual pressing force). Conversely, the ground-engaging member according to the present invention can be disengaged using a simple prying tool. The prying tool may be specially associated with a respective ground-engaging member. However, it may be desirable to be able to use any suitable conventional article as a prying tool, including, for example and without limitation, a screwdriver blade, a coin, and a knife blade.